body{
    background-image: url("../images/login.jpg");
    background-size: cover;
    /*margin-left:50%;*/
    /*margin-right:50%;*/
    /*margin-TOP:100PX;*/
    /*width:10em;*/
}
.top { margin-top: 300px; }
.mycenter{
    margin-top: 18%;
    margin-left: auto;
    margin-right: auto;
    height: 350px;
    width:1000px;
    padding: 5%;
    padding-left: 5%;
    padding-right: 5%;
}